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61.
License plate extraction method for identification of vehicle violations at a railway level crossing
B. K. Cho S. H. Ryu D. R. Shin J. I. Jung 《International Journal of Automotive Technology》2011,12(2):281-289
The primary cause of most railroad accidents is vehicle entry into railway level crossings despite warning messages. To identify
drivers who violate railway level crossing regulations, vehicle license plate recognition can be applied at railway level
crossings. The purpose of this paper is to present an effective method for extracting the license plate region from vehicle
images taken at railway level crossings. The method proposed in this paper uses the variation in the gray-level values across
the image of a license plate. For license plate region extraction, the character region is first recognized by identifying
the character width and the difference between the background region and the character region. The license plate region is
then extracted by finding the inter-character distance in the plate region. In addition, the license plate type is identified
by the difference in the gray-level value between the background region and the character region. The proposed method is effective
in solving the current challenges in extracting the license plate region from the damaged frames of license plates issued
for domestic use, including new types of license plates. According to the experimental results, the proposed method yields
a high extraction rate of 99.5% for vehicle license plates. 相似文献
62.
K. Jang I. Park J. Han K. Lee M. Sunwoo 《International Journal of Automotive Technology》2011,12(4):589-597
Because the FlexRay protocol has more than 70 configuration parameters and these parameters correlate with each other, designing
a FlexRay network is a complex and difficult task. In this study, we propose a design framework that optimizes the two main
FlexRay network parameters that are highly relevant to the application algorithm. The design process is composed of two steps
for optimizing parameters. In the first step, the static slot length is optimized using a frame-packing algorithm. This algorithm
binds network signals into static frames based on their periods and signal groups. In the second step, the communication cycle
length is optimally designed with frame-scheduling algorithm and worst-case reponse time analysis. Based on the frame-scheduling
algorithm, the response times are analyzed. The proposed design framework was applied to a unified chassis control system
as a case study, and the analytical results were verified. 相似文献
63.
64.
H. H. Lee H. W. Bang S. K. Kauh S. I. Kim 《International Journal of Automotive Technology》2011,12(3):351-358
The development of an inner-piston-chamber temperature measurement system is a necessary step in engine development or when
solving other fundamental problems related to automotive engines. There are various pre-existing measurement methods available,
e.g., the linkage method, piston telemetry, templog, and the electromagnetic induction method. In this study, we first redesigned
the coil sensor used in the electromagnetic induction method using PEEK and then used Taguchi methods to reduce the number
of experiments in the development process and finally utilized piston telemetry via Bluetooth to verify the precision and
accuracy of the redesigned PEEK coil sensor and electromagnetic induction method. The results displayed a reproducibility
within 0.5 degrees and an accuracy within 2 degrees Celsius. 相似文献
65.
Seaport research: A structured literature review on methodological issues since the 1980s 总被引:1,自引:0,他引:1
Su-Han Woo Stephen J. PettitDong-Wook Kwak Anthony K.C. Beresford 《Transportation Research Part A: Policy and Practice》2011,45(7):667-685
This study aims to investigate how seaport research has been conducted from the methodological perspective. To this end, this study reviews published port literature for the last three decades (1980-2000s). The investigation primarily categorises the literature according to various methodological issues such as research paradigm, research strategy, base-disciplines, research methods and analysis techniques in order to provide meaningful implications on methodological evolution in seaport research for the period. This study suggests methodological bias in port research to a positivistic paradigm, following a quantitative trajectory moving from conceptual to empirical studies. In addition, the increased use of mathematical modelling and advanced statistical analysis methods is clearly observed. The introduction of advanced analytical tools used in other academic disciplines facilitates discussions in particular research area and amplifies the literature in those areas. This paper also suggests research gaps from the methodological perspective and implications for future port research. 相似文献
66.
John K. Stanley David A. Hensher 《Transportation Research Part A: Policy and Practice》2011,45(8):789-801
Building on a growing research foundation, transport policy makers have begun to associate the ability to be mobile with having a role in the facilitation of social inclusion. However, the further connection to well-being is not as well understood. This paper explores the association between a person’s travel patterns, their risk of social exclusion and self-assessed well-being. Key influences on social exclusion are discussed, with trip making emerging as a significant influence. Trip making is not a significant direct influence on well-being but does exercise an indirect influence through the impact on risk of social exclusion. The modelling process enables a value for additional trips to be estimated, the value being about four times the values derived from conventional generated traffic approaches. Similar high values are found in separate metropolitan and regional case studies, confirming the significance of the results. 相似文献
67.
68.
69.
Ioannis K. Chatjigeorgiou Spyros A. Mavrakos 《Journal of Marine Science and Technology》2007,12(4):218-231
This work considers the second-order sum-frequency diffraction problem for a stationary truncated surface-piercing circular
cylinder in bichromatic waves. The solution method was based on a semianalytical formulation of the second-order sum-frequency
diffraction potential. The boundary conditions were properly satisfied by introducing the “locked” and the “free” wave components
of the nonlinear velocity potential. The method was validated by comparing the calculated results with numerical data previously
reported by other authors. Particular attention was paid to the second-order sum-frequency heave forces and the change in
the wave run-up configuration due to the existence of the lower fluid domain underneath the truncated cylinder. 相似文献
70.
Proshanto K. Mukherjee 《WMU Journal of Maritime Affairs》2007,6(2):147-166
Within the comprehensive body of law encompassed by the International Convention on Safety of Life at Sea, 1974 (SOLAS), there
are two regimes that are topical and outstanding in the current maritime milieu. These are the international safety management
and the international ship and port facility regimes, both characterized by two codes serving as the centre of gravity of
each, namely, the ISM Code and the ISPS Code, respectively. In this article the concept of the code as a legal instrument
is perused following which a critical legal analysis is carried out of the two above-mentioned Codes, including their backgrounds,
the evolutionary process culminating into the regimes and their interrelationships. Several anomalies and inadequacies in
the two regimes are identified but in the final analysis it is concluded that both instruments are salutary additions to the
body of convention law generated by the International Maritime Organization (IMO). They will undoubtedly influence the continuing
development of international law in the field of maritime safety and security. 相似文献